Nicorandil ameliorates hypertension-related bladder dysfunction in the rat

Area of Science:

• Pharmacology
• Urology
• Cardiovascular Research

Background:

• Hypertension is a significant risk factor for bladder dysfunction.
• Ischemia is increasingly recognized as a primary cause of overactive bladder (OAB).
• Nicorandil has shown potential in preventing OAB.

Purpose of the Study:

• To investigate the therapeutic effects of nicorandil on hypertension-related bladder dysfunction.
• To evaluate nicorandil's impact on bladder blood flow, nerve growth factor (NGF) levels, and K(ATP) channel expression in spontaneously hypertensive rats (SHRs).

Main Methods:

• Spontaneously hypertensive rats (SHRs) and Wistar rats were treated with nicorandil (0, 3, or 10 mg/kg) for six weeks.
• Bladder blood flow was measured using the hydrogen clearance method.
• Voiding behavior, contractile responses, NGF levels (ELISA), and K(ATP) channel mRNA expression (real-time PCR) were assessed.

Main Results:

• SHRs exhibited elevated blood pressure, increased micturition frequency, higher NGF levels, and reduced bladder blood flow.
• Nicorandil treatment dose-dependently decreased micturition frequency and NGF levels, while increasing bladder blood flow.
• Nicorandil significantly upregulated K(IR) 6.1 and K(IR) 6.2 mRNA expressions, particularly at the higher dose.

Conclusions:

• Nicorandil effectively prevents hypertension-related bladder dysfunction in SHRs.
• The protective effects of nicorandil are likely mediated by improved bladder blood flow.
• Nicorandil's action on K(ATP) channels may contribute to its therapeutic benefits in OAB associated with hypertension.